This KO8 award will allow an optometrist with a M.S. in vision science to obtain expertise and proficiency in research on myopia, emmetropization, and accommodation. The candidate's long-term goal is to do independent research in this field and eventually have his own laboratory. The long-term goals of the research are to understand how visual stimuli affect the emmetropization process, what biochemical pathways are involved, how this information relates to myopia in humans, as well as how the human accommodative system works. The chick has been the animal that has yielded the most information about emmetropization and myopia development, and is therefore the best animal for this research. The research on human accommodation may provide insight into the eye's emmetropization processes and to provide the candidate with experience studying accommodation in humans. Important skills to be learned will include: creating stimuli that illuminate particular aspects of the visual system, using refractive and ultrasound techniques to analyze the chicks' eye growth, and learning laboratory techniques to analyze the visually-related biochemical pathways. Among these biochemical techniques are: protein assays, high pressure liquid chromatography, ion exchange chromatography, luciferase assay, DNA quantitation, cell culture techniques, and dissection. In the studies on human subjects the applicant will learn to build, calibrate, and maintain electro-optical systems for monitoring fixation and accommodation and create computer generated images stimuli that explore the visual processing that drives accommodation. The KO8 award would also prepare the applicant to become an independent researcher through a series of graduate courses leading to a Ph.D. in Biology with a specialization in Neuroscience. This aspect of the work would include: laboratory work, teaching undergraduate students, and presenting and discussing research findings with colleagues. The supervised research plan will examine the following questions: 1 ) what role does spatial frequency information play in emmetropization (explored experimentally by studies of compensation for spectacle lenses in chicks), 2) can the spatio-temporal characteristics of chickemmetropization and human accommodation be evaluated by the use dynamic random noise stimuli, 3) does retinoic acid participate in emmetropization by influencing the sclera, the choroid, or both.